【作者】 胡雪松；

【导师】 朱正吼；

【作者基本信息】 南昌大学 ， 材料物理与化学， 2010， 硕士

【摘要】 Fe73.5Cu1Nb3Si13.5B9纳米晶磁粉芯的粉体具有粒径小、硬度大的特点,不易模压成型。粉末挤出成型法具有生产效率高、加工设备价格经济的特点,研究粉末挤出成型法制备Fe73.5Cu1Nb3Si13.5B9纳米晶磁粉芯工艺,可以促进磁粉芯的生产效益提高,具有广阔的应用前景。针对Fe73.5Cu1Nb3Si13.5B9纳米晶磁粉芯,本文首先较系统地研究了该磁粉芯的挤出成型工艺,具体设计和制作了一模多腔的成型模具,设计了磁粉芯专用的粘结剂配方,磁粉芯的溶剂脱脂技术,研究了使用双螺杆混炼挤出机挤出成型磁粉芯工艺；其次,针对如何提高挤出成型法磁粉芯的密度问题,研究了粉体级配、改进粘结剂配方、复合FeSiAl粉体对磁粉芯密度的影响情况；最后,较系统地研究了各种挤出成型法磁粉芯的软磁特性,优化出了综合软磁性能最佳的磁粉芯组成和制备工艺。研究表明,使用双螺杆混炼挤出机可以一模多腔地挤出成型Fe73.5Cu1Nb3Si13.5B9纳米晶磁粉芯；设计的“硬脂酸-聚丙烯-石蜡”粘接剂具有粘接效果好、成型方便的特点；300目Fe73.5Cu1Nb3Si13.5B9纳米晶磁粉在合理的挤出工艺下可以挤出成形出密度小于2.5g/cm3的磁粉芯。在300目Fe73.5Cu1Nb3Si13.5B9纳米晶粉体基础上,添加其它粒度的纳米晶粉体,可以有效提高磁粉芯密度,当300目、200目与100目质量比为6:3:2时,相对于300目Fe73.5Cu1Nb3Si13.5B9纳米晶磁粉芯,级配后的磁粉芯密度提高了5%,最高达到3.76g/cm3；采用不同类型的磁粉与Fe73.5Cu1Nb3Si13.5B9纳米晶粉体复合和提高磁粉芯粉胶质量比也可提高磁粉芯密度,当FeSiAl粉体与Fe73.5Cu1Nb3Si13.5B9纳米晶粉体复合、粉胶质量比为10:1时,相对于300目Fe73.5Cu1Nb3Si13.5B9纳米晶磁粉芯,复合粉体磁粉芯的密度提高了31%,达到了4.69g/cm3,是理论密度的60.1%。磁粉芯经脱脂、热处理后,磁粉芯磁导率上升,同时磁粉芯涡流损耗上升,磁粉芯中心频率下移。当磁粉芯配比为“200目FeSiAl粉30wt%+300目Fe73.5Cu1Nb3Si13.5B9纳米晶粉体30wt%”、粉胶质量比为10：1、热处理温度180℃×1hour时,磁粉芯取得最佳的软磁性能,磁粉芯有效磁导率μe达到16.45、中心频率为600kHz、中心频率品质因数Q值为57.5。更多还原

【Abstract】 Fe73.5Cu1Nb3Si13.5B9 nanocrystalline magnetic powder core possessses a small particle size and strong rigidity, therfore, it is difficult to be formationed by pressure molding. Pressure Extrusion Formation method bears high production efficiency and low processing equipment costs. The research studied the production of Fe73.5Cu1Nb3Si13.5B9 nanocrystalline magnetic powder core by Pressure Extrusion Formation method, and found the method could greatly improve production efficiency, with a broad marketing prospects.This paper systematically studied the Pressure Extrusion Formation method, designed a multi-cavity mold, devised an adhesive formula, contrived solvent degreasing techniques, and produced the magnetic powder cores by using the twin screw compounding extruder; Later, to improve the density of the powder core, the experiment mixed with different powder sizes to produce the magnetic powder core, tried to improve adhensive formula, and studied the effects of composite powder FeSiAl had on the magnetic powder core’s density; Finally, the research compared the soft magnetic properties of magnetic powder cores prepared by different pressure extrusion method, optimized the magnetic powder core with desired soft magnetic properties and production procedures.Studies showed that using twin screw compounding extruder could make Fe73.5Cu1Nb3Si13.5B9 nanocrystalline magnetic powder core with multi-cavities, while the "stearic acid-Polypropylene-paraffin" adhesive formula demonstrated good bonding effect and easy formationing.300 mesh Fe73.5Cu1Nb3Si13.5B9 nanocrystalline powder core could be adopted to produce the magnetic powder core of a density less than 2.5g/cm3. Better density can be achieved if other sized powders are added. Mixture of 300 mesh,200 mesh and 100 mesh powders with weight ratio of 6:3:2, in comparison to 300 mesh Fe73.5Cu1Nb3Sil3.5B9 nanocrystalline powder, the core density increases by 5%, with a value up to 3.76 g/cm3. Bonding additionals, or adhensives also can improve the magnetic core density. FeSiAl powder, mixed with Fe73.5Cu1Nb3Si13.5B9 powder, with a weight binder ratio of 10:1, as opposed to powder by the Fe73.5Cu1Nb3Si13.5B9 nanocrystalline only, magnetic core density improves 31%, to 4.69g/cm3.60.1% of theoretical density. After degreasing and heat treatment, the nanocrystalline intergranular’s gap reduces, magnetic conductivityμe rises; At the same time, vortexing turbulence loss of the magnetic powder core increases, its center frequency decreases. Magnetic powder core, of 30%(wt%) 200 mesh FeSiAl powder, plus 30%(wt%) 300 mesh Fe73.5Cu1Nb3Si13.5B9 nanocrystalline powder, with powder/binder (weight ratio 10:1), has the best magnetic properties after heat treatment at temperature of 180℃for one hour. It achievesμe=16.45, the center frequency of 600kHz, Q value of 57.5.更多还原